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<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
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<body>
  <script>

    let x = 10;
    // let y = x++; // 10
    let y = ++x; // 11
    console.log(y);
  </script>
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